Ionic serve not working in Ionic 3

Question

My Ionic info:

cli packages: (/usr/lib/node_modules)

@ionic/cli-utils  : 1.9.2
ionic (Ionic CLI) : 3.9.2

global packages:

Cordova CLI : 7.0.1 

local pack         


        

Answer 1

my configurations for running ionic 3 application:

cli packages: (/usr/local/lib/node_modules)

@ionic/cli-utils  : 1.19.1
ionic (Ionic CLI) : 3.19.1

global packages:

cordova (Cordova CLI) : 8.0.0 

local packages:

@ionic/app-scripts : 3.1.7
Cordova Platforms  : android 6.3.0
Ionic Framework    : ionic-angular 3.9.2

System:

Android SDK Tools : 26.1.1
Node              : v8.2.1
npm               : 5.5.0 
OS                : Linux 4.4

Environment Variables:

ANDROID_HOME : /root/Android/Sdk

Misc:

backend : pro